The overall goal of this research proposal is to determine if staphylococcal slime exopolysaccharide is present in vivo in human coagulase-negative and coagulase-positive staphylococcal disease. The specific aims of this proposal are: (1) to screen clinically relevant staphylococcal isolates for the presence of slime exopolysaccharides, (2) to purify slime exopolysaccharide from the separate antigenic strains of coagulase-negative and coagulase-positive staphylococci and to produce highly specific antibodies, (3) to develop an enzyme-linked immunosorbent assay (ELISA) to detect human antibodies (IgG and IgM) to staphylococcal slime exopolysaccharide and determine their presence in staphylococcal diseases, and (4) to develop an enzyme-immunoassay to detect the presence of slime exopolysaccharide antigens. The methods proposed to accomplish these aims include the antiserum agar technique for identification of encapsulated strains. Ion exchange, molecular sieve affinity chromatography and isoelectric focusing will be used for the isolation of staphylococcal antigens. ELISA and ELISA inhibition methods, cross-immunoelectrophoresis and immunodiffusion will be used to detect and access purity of antigens for analyzing cross-reactivity and as a means of evaluating antibody evolution in animals and humans. Studies of the ultrastructure of the capsular antigens are planned using electron microscopy.